1 c. mayonnaise
4-6 tbsp. ketchup
1 head lettuce
1 avocado
1 lg. tomato
1 can black pitted olives
1 lb. crab or shrimp
1 cucumber

Arrange whole pieces of lettuce nicely on plates. Cut up all other ingredients into bite-size pieces. Put lumps of crab or shrimp in middle of plates on top of lettuce. Arrange other ingredients around crab or shrimp. Mix mayonnaise and ketchup in separate bowl. Spread over salads. Serves 4.